Drought Forces TVA To Alter River Flow for Sequoyah

Drought Forces TVA To Alter River Flow for Sequoyah

BY DAVE FLESSNER
Business Editor

TVA is in hot water again.

A year-old drought in parts of East Tennessee has forced the federal utility to alter the flow of the Tennessee River to ensure the Sequoyah Nuclear Plant can continue operating at full power. Last month, TVA had to briefly limit power generation at Sequoyah when stagnant pools in Lake Chickamauga raised the water temperature above acceptable limits.

"Summer has only now arrived so I'm afraid the problem could get even worse this year," said Dr. Stephen Smith, executive director of the Tennessee Valley Energy Reform Coalition — a TVA watchdog group.

"TVA has a difficult balancing act and so far they seem to be doing OK. But there are a lot of people who reside on the reservoirs upstream who care only about keeping their lakes full or others who want to use the river primarily for power generation. We need to make sure the aquatic life is protected in this process."

TVA insists that it is.

Despite the driest year in more than a decade in most of East Tennessee and North Georgia, TVA has maintained minimum acceptable river flow on the Tennessee River to keep the cooler water from upstream reservoirs flowing into the main channel. That helps keep river temperatures within acceptable limits.

Since last August, the average amount of rainfall in the Tennessee Rivershed above Chattanooga has been 10 inches below normal — the driest period in over a decade. As a result, two of TVA's reservoirs — Nottely Lake in North Georgia and Cherokee Lake in East Tennessee — didn't reach their normal summer pool levels by June 1.

Nottely Lake, which is 9 feet below the preferred level, may never reach normal summertime levels this year because of the rainfall deficit.

Lake users on the East Tennessee and North Georgia reservoirs that feed into the Tennessee River have complained that the low lake levels have hurt their summertime recreation.

But TVA said it must use the Tennessee River for power generation, navigation and environmental quality — in addition to recreation.

"I can certainly understand why residents are upset about the level of Lake Nottely this summer," said Gregory W. Lowe, manager of river scheduling for TVA.

"We at TVA are disappointed too."

In the summer, TVA prefers to use its hydro units during peak power demand periods when electricity is more valuable. But to maintain enough water flow for Sequoyah and to protect aquatic life, TVA has had to use a more limited flow throughout the day.

TVA changed its pattern of river flow last month after Sequoyah was forced to reduce its power generation by 16 megawatts when the river water TVA uses to cool water for the nuclear unit got too hot. TVA is allowed to raise the river temperature only 3 degrees in an hour.

TVA had no water flow on Chickamauga Reservoir for over

Cooling towers stand tall at TVA's Sequoyah Nuclear Plant near Soddy-Daisy. Due to an extended drought, the agency has been forced to alter the flow of the Tennessee River to maintain proper water temperatures for the power plant's discharge.

TVA would prefer to release most of the water through the river during the summer. But the water is needed to provide flows necessary to lower the water temperature and maintain the river's temperature and water quality. "The water behind the dams can operate more efficiently, it gets hotter, it gets more valuable the hotter it gets," Dr. Smith said. "TVA can't emphasize the situation in a manner that ensures both environmental quality and helps the nuclear plants at critical production is even more critical."